4 research outputs found
Distribution of velocities and acceleration for a particle in Brownian correlated disorder: inertial case
We study the motion of an elastic object driven in a disordered environment
in presence of both dissipation and inertia. We consider random forces with the
statistics of random walks and reduce the problem to a single degree of
freedom. It is the extension of the mean field ABBM model in presence of an
inertial mass m. While the ABBM model can be solved exactly, its extension to
inertia exhibits complicated history dependence due to oscillations and
backward motion. The characteristic scales for avalanche motion are studied
from numerics and qualitative arguments. To make analytical progress we
consider two variants which coincide with the original model whenever the
particle moves only forward. Using a combination of analytical and numerical
methods together with simulations, we characterize the distributions of
instantaneous acceleration and velocity, and compare them in these three
models. We show that for large driving velocity, all three models share the
same large-deviation function for positive velocities, which is obtained
analytically for small and large m, as well as for m =6/25. The effect of small
additional thermal and quantum fluctuations can be treated within an
approximate method.Comment: 42 page
Performance and behavior of dairy calves fed diets containing milk and citric flavor agents Desempenho e comportamento de bezerros leiteiros alimentados com dietas contendo agentes de flavor lácteo e cítrico
While young ruminants prefer milk aroma and researches about this theme are being developed, the use of citric aroma, very appetized for older ruminants, are low utilized to young animals. This work aims to compare the influence of milk and citric flavor agents on the diets of nursing dairy calves. In this trial, 12 animals of Holstein breed were distributed in a randomized block design with four treatments (concentrate without flavor agent, concentrate with milk flavor or citrus flavor, and concentrate with milk plus citrus flavor agent) and three repetitions. The parameters evaluated were: concentrate dry matter intake (CDMI), hay dry matter (HDMI), milk dry matter intake (MDMI) and total dry matter intake (TDMI), average weight gain (ADWG), feed conversion (FC), initial (IBW) and final body weight (FBW), initial thoracic perimeter (ITP) and final thoracic perimeter (FTP), initial abdominal perimeter (IAP) and final abdominal perimeter (FAP), initial withers height (IWH) and final withers height (FWH) and animal behavior. The CDMI, HDMI and TDMI, as well as IBW, FBW, ITP, FTP, IAP, FAP, IWH and FWH did not show differences (P>0.05). The averages daily gain and feed conversion showed no differences, with means of 0.55 kg/animal and 2.09, respectively. The diets did not affect animal behavior parameters (P>0.05).<br>Enquanto ruminantes jovens preferem aroma de leite e pesquisas sobre este tema são desenvolvidas, o uso de aroma cítrico, muito apreciado por ruminantes adultos, é pouco utilizado para animais jovens. Portanto, com este trabalho visou-se comparar a influência de aromas lácteo e cítrico nas dietas de bezerros na fase de aleitamento. Neste experimento foram utilizados 12 animais da raça Holandesa, distribuídos em um delineamento de blocos ao acaso, com quarto tratamentos (concentrado sem palatabilizante e concentrado com palatabilizante lácteo, cítrico e lácteo mais cítrico) e três repetições. Foram avaliados o consumo de matéria seca do concentrado (CMSC), do feno (CMSF), do leite (CMSL) e do total (CMST), ganho médio diário (GMD), conversão alimentar (CA), peso inicial (PI) e final (PF), perímetro torácico inicial (PTI) e final (PTF), perímetro abdominal inicial (PAI) e final (PAF), altura de cernelha inicial (ACI) e final (ACF) e o comportamento animal. O CMSC, CMSF e CMST não apresentaram diferenças da mesma forma que as mensurações de PI, PF, PTI, PTF, PAI, PAF, ACI e ACF. O ganho médio diário e a conversão alimentar não foram diferentes, obtendo-se médias de 0,55 kg/animal e 2,09, respectivamente. As dietas também não influenciaram os parâmetros de comportamento animal (P>0,05)